SIMPLIFIED SMOKE FILLING EQUATION FOR A SINGLE ENCLOSURE

Abstract

In this article, we would develop a fix calculation sheet of simplified smoke filling hand-calculable formula for single compartment close system from mass and energy balance. This type of simplified formula that only knows three parameters - fire growth rate, floor area, and ceiling height - then could easy obtain times for critical smoke layer height (1.8 meter above the floor). This calculation sheet can be used in any single compartment without restriction. Next we compared with otheCIBSEr smoke filling equations (include CIBSE, NFPA92B unsteady and steady fire smoke filling) and zone models (CFAST) to verify simplified formula accuracy. From the results of case studies it can be known that except NFPA92B steady fire smoke filling equation (Morgan suggests a heat release rate per unit floor area for office building of 225k W/m(sup)2), other smoke filling equations are very approximate with an error range of +/- 5%, because the fire load is too large for conservation. And in this article we did also suggest ideal values for steady fire smoke filling. At last, we hope this fixed calculate sheet of simplified hand-calculable formula would be useful for practitioners in fire safety engineering design of building for evacuation safety from smoke.